Surgical Pearls in Molteno3® Implantation Enhancing outcomes and optimizing surgical utility

Molteno3® is no stranger to the glaucoma world. This glaucoma drainage device (GDD) has been shown to deliver consistent, long-term intraocular pressure (IOP) control in cases of severe and complex glaucoma. US ophthalmologist Dr. Joseph F. Panarelli, who is an authority in GDD, shared his take on implanting the Molteno3.

In order to ensure optimal outcomes, Dr. Joseph F. Panarelli has fine-tuned his surgical technique for Molteno3 implantation.

He starts the procedure with the placement of a 6 o’clock micro traction stitch that allows for enhanced exposure. “I like to

by Tan Sher Lynn

open up a horizontal meridian and continue by dissection up past the twelve o’clock area and maybe go just an additional clock hour before making a second relaxing incision. The superior temporal quadrant is my preferred quadrant of choice for implantation and if it is not suitable I will move to the inferior nasal quadrant,” he said.

In cases where the patient has more scarring due to prior subconjunctival minimally invasive glaucoma surgery (MIGS), he elects to free up the scar tissue before proceeding to hook both the superior lateral rectus muscles and free them from the Tenon’s attachments, after which he places the Molteno3 in the superior temporal quadrant.

“One of the nice things about the Molteno3 is that it really hugs the globe nicely, so as you tuck it back into the quadrant it really doesn’t move forward that much. This makes it easier when you perform the placement of the temporary ligature, to allow for time for the implant to encapsulate,” he said.

“It’s very important for non-valved GDDs to have the ligature in place and it needs to be water-tight,” he added, noting that there should be no movement of fluid posterior to the ligature upon priming the eye with balance salt solution.

“The GDD needs to be secured approximately eight to ten millimeters posterior to the limbus. The more posterior you can place the GDD, the better the flow. There’s also a lower likelihood of postoperative strabismus. The knots of the non-absorbable suture need to be rotated into the eyelets, so that we don’t end up with erosion or extrusion of these knots down the road,” he advised.

After the GDD is secured in place, he moves on to implant the tube into the anterior chamber. Firstly, the eye is pulled back into primary position, before trimming the tube with a Westcott scissors, making sure not to over-trim the tube.

He then bends a twenty three gauge needle and makes a tunnel track into the eye to insert the tube, ideally about two millimeters into the anterior chamber. “We want to make sure it’s parallel to the iris plane and far away from the corneal endothelium. Given that this is a non-valved GDD we need some method to control the pressure early on so I’ll pass a ten o’clock vicryl stitch to the occluding ligature. I want to see a nice percolation of fluid through that fenestration,” he said.

50 Years of Innovation for Superb Efficacy

First introduced in 1966 by Prof. Anthony Molteno (who invented the world’s first glaucoma drainage device), the Molteno3 has gone through various evolution and refinement until it reaches the form that it is today —the third generation of Molteno.

Thus, far from being an outdated technology, the Molteno3 technology actually reflects a history of extensive research into bleb formation and function, and is considered by many to be the gold standard in GDD technology.

With a contoured plate, the novel design of the Molteno3 is designed to hug the sclera perfectly. At just 0.4 mm, it is also the slimmest plate on the market. This smooth polypropylene plate reduces the risk of fibroblast attachment, supporting better bleb formation over the longterm. It slides easily between tissue planes and adjacent extraocular muscles, allowing for a shorter, more simplified surgical procedure with less patient discomfort. Additionally, repositioning is relatively easy to achieve the desired outflow when needed.

For more information on Molteno3, visit: https://glaucoma-molteno.com.

Then, a corner patch graft is sutured in place over the tubing to prevent erosion of the tube down the road. Dr. Panerelli notes that he likes to tunnel the tubes closer to twelve o’clock as he is able to obtain better coverage with the upper eyelid and a lower likelihood of tube erosion in the future.

The final step is to close the conjunctiva. “At this point I will often loosen the speculum, bring the eye back up into the primary position and try to advance the conjunctiva up to the limbus. Once it is in place I will close each of the relaxing incisions. I typically try to get deep bites for the first two or three bites so that the tissue is less likely to cheesewire and then take more superficial bites as I am getting further posterior from the limbus,” he said. Once a nice closure is obtained, he then injects the antibiotic and steroid mixture beneath the inferior conjunctiva and palpates the globe to make sure that the desired pressure is achieved.

Contributing Doctor

Dr. Joseph F. Panarelli is a US-based ophthalmologist specializing in the treatment of adult and pediatric glaucoma. He is certified by the American Board of Ophthalmology and is a member of the American glaucoma Society and American Academy of Ophthalmology. He is a glaucoma specialist at NYU Langone Health, where he is also an associate professor of the Department of Ophthalmology at NYU Grossman School of Medicine; program director of the Glaucoma Fellowship Program; and director of the Division of Glaucoma Services, Department of Ophthalmology. He chose to specialize in glaucoma because it allows him to provide ongoing medical care and surgical treatments to patients to improve their quality of life. He has published several new surgical techniques as well as new findings comparing traditional glaucoma procedures to current ones. He has also been part of numerous clinical trials for new surgical devices for eye procedures.

Joseph.Panarelli@nyulangone.org